Process of dehydration of alcohol for carburants



Patented Feb. 21, 1928.

UNITED STATES PATENT OFFICE.

ELOI RICABID ANDHENRI GUINOT, OI MELLE, FRANCE, ASSIGNOBS '1'0 SOCIETEBICARD, ALLENET & 0111., OF DISTILLERIES DES DEUX-SEVRES, -MELLE, DEUX-SEVRES, FRANCE.

PROCESS O1 DEHYDRATION -01E ALCOHOL FOR GAIRIIBU'R..Alltl'l!S NoDrawing. Application filed September 27, 1923, Serial No. 665,188, andimBelgium September 30, 1922.

It is a known fact that commercial alcohol is soluble in gasoline in allproportionsonly when it has a high degree of purity.

When use is made of alcohol for instance 5 at 90 degrees Gay-Lussac, itbecomes necessary to add special solvents to the mixture of alcohol andgasoline.

On the contrary, it is sufficient to employ alcohol having a strength inthe vicinity of 97 .5-98 degrees G. L. in order that it shall be solublein all proportions and at sufliciently low temperatures.

But the rectifying process will not produce alcohol above 96.5 G. L. Inorder to remove the last portions of'the water which are retained withgreat tenacity by the alcohol, the substances in common use for thedehydration of organic liquids, such as sulphate of soda and carbonateof potash, are practically without effect. Powerful chemical reactionsmust be employed in orderto destroy the aflinity between water andalcohol, the water being removed by such substances as lime and baryta;5' According to our researches, water can be removed from fuel alcoholin a suflicient and very simple manner by utilizing the reduction of theaflinity between water and alcohol brought about by the addition of asuitable quantit of gasoline, and it is this process of dehy rationwhichconstitutes the object of our present invention.

The above-mentionedwater-absorbing neu not dissolve in the carburantemployed.

. Mention may be made of carbonate of potash, carbonate of soda,sulphate of soda, sulphate of copper,'chl0r1de of magnesium, sulphate ofmagnesium, and thelike, such substances being used singly or mixedtogether.

Since water is removed from the alcohol 1n consequence of a sort ofrupture of equilibrium when the alcohol is mixed with gasoline, theconditions of the experiment are preferably modified according to thequalit of the gasoline and the degree of the alcoho so as to obtain themaximum speed of reaction.

Alcohol may thus be mixed with gasoline to which the proper quantity ofdehydrating substance has been preliminarily added, or inversely thegasoline is mixed with alcohol containing .the dehydrating substance, orfurther, we may add the dehydrating substance to the lifiluids whichhave been prehminarily mixe I Denaturedv alcohol can beiemployed in thesame manner as ordinary alcohol.

Example I volumes of light gasoline, density 0.708. 25 volumesof'alcohol at 95.5 degrees G. L. These substances are not miscible, and75 when used at 20 degrees centigrade they will se arate into twolayers.

y agitating with two parts of carbonate of potash, the mixture willinstantly become clear. The point at which it becomes turbid so isreduced to +4 degrees.

If the dehydration is to be still further carried out, it is simply'necessary to pour off the liquid after settling and again agitate itwith a small amount of carbonate of otash, and the point at which itbecomes 'tur id is diminished below -l7 de ces- This is the equivalentof amixture 0 acted with alcohol at 97 .5-98 degrees G. L. I

The rapidity of the dehydration will enable the use of a continuousoperating method on a manufacturing scale.

Example I] The mixture'consists of I 55 volumes of alcohol at 95.5degrees G. L.' 45 volumes of gasoline (of what is termed the touringtype) y Density 0.728 at +15 degrees C. p This mixture is clear at +23degrees C. 100

and becomes cloudy at +22 degrees. When the clear liquid is agitatedwith a small quantity of carbonate of potash, it is observed at oncethat the salt absorbs moisture, and it tends to adhere to the sides ofthe vessel; the liquid after settling will become cloudy only at +12degrees.

By a second treatment with dry carbonate the point at which the liquidbecomes turbid is reducedto +2 degrees. Example [I I The mixtureconsists of volumes of alcohol at 95.5 degrees G. L. a 90 volumes ofheavy gasoline, density 0.7 53.- At the ordinary temperature the mixtureseparates into two layers. When agitated with a. small quantity ofSolvay carbonate of soda it becomes clear, while the salt be comesviscous, showing that it has absorbed.

water.

After settling the carburant is'clear at the ordinary temperature, butbecomes cloudy at +16 degrees.

' If the dehydration i. to be San further carried out, the liquid isagain'agitated with a small amount-of the Solvay salt or with carbonateof potash.

' V In the three examples above-mentioned,

the dehydrating. salt can be readily recovered. Preliminarily, werecover by distillation the very small quantity of liquid which the salthas absorbed. I

'Our said process for dehydration of alcohol' and gasoline mixtures isrendered still more efiective by operating under the fol lowingconditions.

(a) Upon continuously circulating a mixture of alcohol'and gasoline(which are miscible or not) in avessel, or several vessels in series,containing one of the said Water-absorbing salts or a mixtureof'thesame, the

liquid mixture being supplied at one end of the vessel (or series ofvessels) and issuing at the other end, we obtain a dehydration carriedout to the extreme limit in the minimum time, inasmuch as the mixtureunder dehydration is constantly in the presenceand in a repeatedmannerof a great excess of water-absorbing substances which arecontinually moreanhydrous.

r A (b) When the mixture of alcohol and gaso line to be dehydrated istreated with small quantities of one or more liquids of such nature asto unify the heterogeneous mixtures of alcohol and gasoline, thedehydration of the alcohol will be carried out to a greater extent thanwithout the use of such liquids;

we may mention by way of example -sul-' phuric ether, benzene and itshomologues, .propylic, butylic and amylic alcohol and their homologues,cyclohexanol, and like substances. I

(c) A continuous circulation of the liquid mixture to be dehydrated incontact with a" great excess of the water-absorbing substance containedin the said vessel or vessels will produce a progressive absorption ofthe water by the absorbing body from inlet to outlet of the liquid, sothat the absorbing body will usually be brought to a concen-. tratedsolution at the inlet of the liquid, and will remain in the practicallyanhydrous state at the outlet. I

Mixtures of alcohol and hydrocarbon will act in a similar manner tomixtures of alcohol and gasoline asconcerns the dehydration.

- E sample IV.

Let us consider the heterogeneous mixture consisting of:

liters of gasoline of theabove mentioned touring type, density 0.728.

20 liters alcohol at degrees.

By agitatin the mixture three different times with 2 ilograms ofanhydrous carbonateof otash, we obtain a clear liqu'idresembling t e oneproduced by the use of 98.1 degree alcohol; we employ 6 kilo rams ofcarbonate of potash which is broug t to the state of moist salt, andthis can be recovered y heating.

But if the said mixture is circulated in a set of for instance 6vessels, each'of which.

has 8-liters capacity and contains anhydrous carbonate of potash (mixedif necessary with a suitable inert substance such as pumice stone so asto facilitate the circulation of the liquid), the mixture issuing fromthe apparatus is similar to theone prepared by the use of 99.5 degreealcohol; and we therefore gain 1.4 degree G. L. relative to the methodof successive agitations. Further, only 1 kilogram of carbonate ofpotash is employed, this havingabsorbedabout 1 liter of water to form aconcentrated solution. The carbonate of ing. p

' Example V.

We employ the same mixture asin the precedin case:

80 ii densit 0.728.

20 liters of alcohol at 95 degrees.

If we"preliminarily add to this mixture 2 liters of sulphuric ether, andagitate in three different operations with 2 kilograms of. anhydrouscarbonate of potash, we obtain a liquid mixture analogous to the oneprepared with 98.6 degree alcohol.

The addition of a small quanit of ether has therefore increased "thedehy ration by 0.5 degree G. L. over the receding process. When the saidmixture with the addition of 2 liters'of ether) is circulated inthevess, els as mentioned in Example I, the resulting llqllld. mix ureis'analogous to the one produced,b t e use-of alcohol at 98.7 degrees,

so that y. adding asmall quantity of ether potash is recovered by heat--ters of gasoline of. the touring type,

we can extend the dehydration by 0.2 degrees G. L. as compared to theprocess not employing ether.

Emample VI.

ples IV to VI are subject to certain varia-..

tions according to the character of the gasoline products and thehydrocarbon employed.

As stated at the beginning of this specification, the special object ofthe present invention is the dehydration of alcohol for carburants, andit is based upon the discovery that, when the alcohol is mixed with thehydrocarbon previously to the treatment thereof with the dehydratingsalts, the action of the latter is increased in a very large measure; orin other words that the absorption of the water thereby is much morerapid and more complete than when there is no hydrocarbon present. Hencethe invention makes possible the very ready combining of alcohol withgasoline, or other hydrocarbon having a boiling point approximating thatof gasoline, which mixture can be used directly as a carburant. Thegasoline therefore serves a twofold purpose: First, it.

greatly expedites and facilitates the dehydration of the alcohol; andsecond, it makes possible by a single operation not merely thedehydration of the alcohol but the production of a carburant suitablefor use in explosion engines.

-It follows from What has been said above that the process has-noreference to the de hydrating of gasoline or other hydrocarbons. Indeed,inasmuch as gasoline does not dissolve water it does not need to bedehydrated; though gasoline or other hydrocara bon may hold dropsofwater in suspensionin the colloidal state, which is uite a differentmatter. It should be state however, in

this connection, that the present invention is applicable specially togasoline, and to other hquid hydrocarbons having a boiling point I aproxim'ating that of gasoline.

urther it should be stated that the dehydrating agents herein specifiedare inactive and insoluble upon both constituents of the mixture. Theyserve only to absorb the water, and efiect no other change.

What we claim is:

1.- The process which consists in mixing alcohol with a liquidhydrocarbon and subjec'ting the mixture to the action of a neutraldehydrating agent.

2. The process which consists in mixing alcohol with a liquidhydrocarbon and continuously circulating the mixture over a waterabsorbing salt.

3. The process which consists in mixing alcohol with a liquidhydrocarbon, adding to said mixturea small quantity of unifyingsubstance, and then subjecting the mixture to the action of adehydrating agent.

4. The process which consists in mixing alcohol and gasoline, and thenpassing the mixture through a mass of a dehydrating salt.

5. The process which consists in subject- 1 ing hydrated alcohol to theaction of a dehydratin agent in the presence of a liquid hydrocar on. v

6. The process of producing a carburant suitable for use in explosionengines which process consists in first mixing a liquid hydrocarbonhaving a boiling point approx1- mating that of gasoline with hydratedalcohol, and then subjecting the mixture to the action of a dehydratingagent.

suitable for use in explosion engines, which process consists in firstmixin a liquid hydrocarbonQwith hydrated alco 01, and then ification.Specq ELOIRICARD.

7. The process of producing a carburant I ?IIEN RI'GUINOT. I

